Since spring 2015, PTV Group has been involved in the research project FLOW – “Furthering less congestion by creating opportunities for more walking and cycling”. The project aims at researching and demonstrating how measures for walking and cycling can help to reduce urban congestion, including congestion of motorized traffic.
Achieving this may sound challenging for a number of reasons: firstly, the maximum speed. The ability to accelerate, as well as the flexible use of cars, clearly make cars appear superior over all other means of mobility. Secondly, the idea of zero-sum games – what is given here, has to be taken there – intuitively is very convincing, sometimes more convincing than actually is justified. Finally, an overly identity-based thinking (“I, car driver”, “we cyclists”, “these pedestrians”) often blurs our view on how easily one can choose a different way to move if there is an appropriate alternative.
Thinking about the aims of FLOW, issues like network-wide shifts and time elasticity of demand and other rather complex phenomena may come to mind at first. We then asked ourselves, how could we demonstrate the aims of FLOW as simply as possible. The result is this simulation animation using PTV Vissim and Viswalk, in which 200 people each start moving at the same time on equally wide links to pass a cross section.
200 people each pass a traffic signal in different modes. For the simulation of all typical values for desired speed, accelerations, etc. were used. There is also a raw version without fast forward.
The images of the video may remind you of numerous photographs which – created with a similar reasoning – demonstrate the very different spacial requirements of an identical number of people, depending on if they are moving in cars, trams or as pedestrians or cyclists. However, this video additionally shows how this different spacial requirement in combination with different maximum speeds and acceleration ability translates into a flow and from that, into the time required to complete the process. The resulting numbers for required space and time can be easily approximately calculated if one knows the characteristic numbers which form the basis of the process. Thus, the information in the video is surely not new. Still, such an animation is more memorable and relatable than a table with numbers (which nevertheless you find at the end of this contribution).
In this way, it becomes obvious how the huge space required for one person in a car in a dense urban environment, leads to a situation where the advantages of cars are no longer relevant and the assumption that the ability to move fast also implies – compared to other means of mobility – shorter travel times is not necessarily correct anymore.
There are two strategies to react on this discovery: firstly, car traffic could be assigned more urban space. However, this implies that the density of other urban functions, which increasingly – as distinguished from traffic areas – are seen as the actual factors defining urban life, is reduced.
As examples of such strategies, one might first think of wide urban arteries with six, eight or even more lanes, such as those found in today’s metropolitan agglomerations. A different, although small example is more impressive due to its irony. In the 130th anniversary of the invention of the car it also suggests itself as anecdotal example, even more so in the blog of a company from Karlsruhe. Carl Benz was born in 1844 in Mühlburg (now part of Karlsruhe) and in 1886 was the first to submit a patent application for a “horseless carriage” or “petroleum motor driven bicycle”. Since young Carl relocated frequently in his childhood, knowledge about his exact birth place was lost. When in 2012 the address Rheinstraße 22 was reconstructed, it became apparent that the house the inventor was born in was torn down in the late 1950s to make way for the widening of the road in front (the Rheinstraße).
The second, converse strategy for urban traffic is to place emphasis on other traffic modes which require less space than the car and so reduce congestion of cars, which brings us back to the FLOW project.
The FLOW project cities collaborate with scientific institutes and universities, interest groups, mobility and communication agencies, and technical partners, to which PTV Group belongs. In particular, PTV Group contributes to the development of a method to assess measures for cycling and walking, with a special focus on the potential for congestion reduction. Furthermore, they study the requirements from the cities and their projects for the planning software and extend it where required. Consequently, in PTV Visum 16, it will be possible to consider bike sharing systems.
- Website of the research project FLOW
- Daimler AG: ”Mercedes-Benz Classic: Fresh clues to the birthplace of Carl Benz”
(original story in German language: ”Neue Erkenntnisse aus dem Kirchenbuch: Das Geburtshaus von Carl Benz in Mühlburg” by P. Pretsch on Karlsruhe.de)
Numbers from the video
This post is also available in: German